Two reports are raising concerns about beryllium contamination at the Bannister Federal Complex in Kansas City, Missouri. The Bannister Federal Complex, part of which was used to make parts for nuclear bombs, has been the focus of growing alarm over pollution and worker health, according to the Kansas City Star. The complex is occupied primarily by the General Services Administration and the Department of Energy. Honeywell Federal Manufacturing & Technologies, a private contractor, operates the manufacturing area.

The first report was conducted by an independent consultant and found beryllium contamination in a 230,000-square-foot area of the plant. It doesn’t specify if beryllium dust falls within federal safety standards or if workers were exposed to hazardous levels of the very toxic metal, the Star said.

The second report is even more disturbing, finding that an unusually high number of Kansas City plant workers have become ill from exposure to beryllium. That report was prepared by the energy departmentâ€™s own Office of Health, Safety and Security, the Star said. It found the rate of beryllium-related illnesses was higher than expected considering the limited amount of beryllium that plant officials said was used over several decades.

According to the Star, federal officials who oversee the plant have refused to give details about the beryllium contamination and cleanup efforts. However, the federal government acknowledges that workers at the Kansas City plant have gotten chronic beryllium disease or lung cancer. It has paid out $28 million in compensation and medical benefits for toxic exposures, including beryllium.

According to the Kansas City Star, GSA and the nuclear security agency have been negotiating over a cleanup of the contaminated 230,000 square foot area for about eight years. But among other things, they can’t agree on the level of cleanup needed.

Questions also remain about how thorough a beryllium cleanup was done throughout the rest of the plant, the Star said. A decade ago, it was found that significant contamination had occurred and many workers had been exposed. The federal government ordered the plant to clean up excessive levels of beryllium dust, and energy department officials said the cleanup was complete. But according to the Star, it’s difficult to know how complete the cleanup really was.

Beryllium is a know carcinogen, and is linked to a number of serious diseases. It can cause chronic beryllium disease, which can scar the lungs and affect lymph nodes, liver, kidneys and heart. Chronic beryllium disease can take as long as 30 years to develop.